Auto dealer web

I do web sites for auto dealers. I need a script(?) where the dealer can make changes to his online inventory using just his web [login to view URL] of like the various classified ad programs aval. Dealer must be able to edit ads, delete ads and upload photos. The script must be re-usable..so I can use it with more then one web site. There is a program out there that is similar to what I need (Online Arts Showroom)but it is priced way above my means and it is a one time only license) + I really dont need all the features. Just the one that lets the dealer make his own changes. ## Deliverables Complete source code of all programming work done installation if possible ## Deadline information asap